1. Field of the Invention
The present invention relates to a liquid processing apparatus for applying a predetermined liquid processing or a predetermined drying processing to various substrates such as a semiconductor wafer and a liquid crystal display (LCD) substrate.
2. Description of the Related Art
In the manufacturing process of, for example, a semiconductor device, used is a wafer cleaning apparatus for cleaning a semiconductor wafer used as a substrate by using a cleaning liquid such as a predetermined chemical liquid or a pure water so as to remove contaminants such as particles, an organic contaminant, and metal impurities from the wafer or for drying the wafer by removing liquid droplets from the wafer by using an inert gas such as a nitrogen gas (N2) or a volatile and highly hydrophilic IPA vapor. Known is a wafer cleaning apparatus of this type, wherein a plurality of wafers are introduced into in a wafer cleaning/drying chamber for processing these wafers in a batch system.
A wafer cleaning apparatus is disclosed in, for example, U.S. Pat. Nos. 5,784,797 and 5,678,320. The wafer cleaning apparatus disclosed in each of these prior arts includes a rotor having wafers held therein, a wafer cleaning/drying chamber having a wafer delivery port formed on the front wall facing a wafer transfer arm when the wafer transfer arm has been moved toward the wafer cleaning/drying chamber, and a wafer cleaning mechanism wherein a wafer chuck of the wafer transfer arm is moved into the wafer cleaning/drying chamber through the wafer delivery port so as to deliver the wafer held by the wafer chuck into the rotor, or wherein the wafer held by the rotor is received by the wafer chuck.
Conventionally, the wafer cleaning/drying chamber itself was of a hermetic structure so as to prevent leakage of the cleaning liquid. However, the housing having the wafer cleaning/drying chamber arranged therein was not of a hermetic structure.
It should be noted in this connection that the cleaning liquid may possibly leak to the outside through, for example, the joints of the members constituting the wafer cleaning/drying chamber. Further, where the wafer rotated at a high speed has been broken, the wafer cleaning/drying chamber may be damaged by the broken pieces of the wafer so as to cause leakage of the cleaning liquid. Furthermore, the process liquid leaking from the housing may leak further from within the cleaning process chamber to the outside.
The process liquid leaking from the wafer processing/drying chamber or from the housing is likely to bring about a disorder in the mechanical system or the electrical system arranged within the wafer cleaning apparatus. Further, when the leaking cleaning liquid is flammable, a fire may breaks out in the wafer cleaning apparatus. Further, the broken pieces of the wafer cleaning/drying chamber may be scattered so as to damage the other adjacent processing sections. If the damage is extended to the entire wafer cleaning apparatus, it takes much time to repair the wafer cleaning apparatus, and the repair becomes costly.
What should also be noted is that it is necessary to maintain periodically the wafer cleaning mechanism. When the wafer has been broken or leakage of the cleaning liquid has taken place during the cleaning process, it is necessary to clean or repair the wafer cleaning mechanism by interrupting the cleaning process. Therefore, it is desirable that the wafer cleaning mechanism can be easily accessed. However, in the wafer cleaning mechanism disclosed in U.S. Pat. Nos. 5,784,797 and 5,678,320 quoted above, the wafer cleaning mechanism can not be accessed except from the front wall of the housing when the rotor is attached or detached for the maintenance purpose. Therefore, the maintenance is not easy.
A first object of the present invention is to provide a liquid processing apparatus excellent in reliability, wherein an accident occurring in the housing does not affect another mechanism or process section within the liquid processing apparatus.
Further, a second object of the present invention is to provide a liquid processing apparatus that facilitates the access to the liquid processing mechanism, wherein a target object to be processed is subjected to a liquid processing so as to facilitate the maintenance.
According to a first aspect of the present invention, there is provided a liquid processing apparatus, comprising a liquid processing section for performing a liquid processing by supplying a predetermined process liquid to a target object while rotating the target object; and a housing for housing said liquid processing section; wherein said housing has a hermetic structure which is substantially shielded from the outside.
In the liquid processing apparatus according to the first aspect of the present invention, the housing for housing the liquid processing section for applying a liquid processing to the target object has a hermetic structure. Therefore, even if the process liquid leaks from the process chamber, it is possible to avoid such an accident that the leaking process liquid flows into another process section and is diffused so as to damage the other process section.
Further, even when the process liquid leaking from the process chamber brings about a fire within the liquid processing section, it suffices to fight the fire only within the liquid processing section so as to make it possible to prevent the other process section within the liquid processing apparatus from catching fire and receiving damage.
Further, even when the target object and the apparatus such as a process chamber within the liquid processing section have been broken and the broken pieces have been scattered, the broken pieces are prevented from being scattered from within the housing. As a result, the other process sections constituting the liquid processing apparatus are prevented from being damaged. It follows that it is possible to restore the entire liquid processing apparatus to a usable state by repairing only the damaged liquid processing section, thereby reducing the repairing time and the number of parts that are replaced so as to reduce the cost required for repairing the liquid processing apparatus.
What should also be noted is that, since the housing has a hermetic structure, the housing is unlikely to be affected by the other process sections and by the external environment so as to make it possible to maintain a constant environment, e.g., a constant temperature, within the housing. It follows that, in the case of using a process liquid of a high temperature, it is possible to set an environment within the housing in accordance with the temperature of the process liquid so as to inhibit the cooling of the process liquid. As a result, it is possible to carry out an effective liquid processing by fully utilizing the characteristics of the process liquid.
According to a second aspect of the present invention, there is provided a liquid processing apparatus for applying a predetermined liquid processing to a target object to be processed, comprising a cylindrical process chamber for housing the target object; and a liquid processing mechanism for performing a liquid processing by supplying a predetermined process liquid to said target object while rotating the target object housed in the process chamber; wherein the liquid processing mechanism is accessed from at least the side wall.
According to a third aspect of the present invention, there is provided a liquid processing apparatus for applying a predetermined liquid processing to a target object to be processed, comprising a liquid processing section including a cylindrical process chamber for housing the target object and a liquid processing mechanism for performing a liquid processing by supplying a process liquid to said target object while rotating said target object; a container delivery section for delivering a container capable of housing said target object; a transfer mechanism for transferring the target object between said container delivery section and said liquid processing section; and a detachable panel providing a partition wall between said container delivery section and said liquid processing section; wherein it is possible to gain access to the liquid processing mechanism from the sideward direction of said process chamber and from the direction of said container delivery section by detaching said panel.
In the liquid processing apparatus according to the second and third aspects of the present invention, it is possible for the worker or the cleaning machine to access the liquid processing mechanism or the liquid processing section in the event of the maintenance for recovering a malfunction or for cleaning the liquid processing mechanism from at least the side wall, or from the front wall, if need be. Therefore, the maintenance becomes easy. It follows that the maintenance time can be reduced, and the cleaning or the like can be performed in detail in the back region and the small spaces.
Further, in order to improve the maintainability in the cleaning of, for example, the floor of the casing having the liquid processing mechanism and the liquid process section installed thereon, it is possible to maintain a good environment inside the casing, thereby decreasing the amount of the particles or the like attached to the target object to be processed so as to improve the quality of processed target object. Incidentally, such a maintainability can be further improved by using a sliding type chamber.